Conventional zoom mechanisms of a camera having a zoom function include a power-zoom mechanism which is realized by driving a motor, and a manual zoom mechanism which changes magnification by manual operation. In general, a camera employing the power-zoom mechanism has an advantage of enabling to change the magnification with ease by operating zoom buttons provided respectively for a telephoto direction or a wide-angle direction or a lever. Meanwhile, in the manual zoom mechanism, rotating a zoom ring provided in a lens portion enables to change the zoom magnification for the amount of rotation in a rotated direction. This provides an advantage of intuitive and meticulous adjustment. In view of this, proposed is a zoom lens driving method, which employs a zoom ring for operation that takes advantage of its operability, and which performs actual lens driving by controlling a power-zoom in accordance with operation of the zoom ring (e.g., Japanese Patent Application Laid-Open No. 5-188268 and No. 7-27965).
However, in a case where a zoom ring is adopted as a zoom operation member, a camera having a high-magnification zoom function has a long zoom lens moving distance from the telephoto end to the wide-angle end. Therefore, the time required to keep rotating the zoom ring is long, imposing burdensome zoom ring operation on a user. Furthermore, since achieving a desired angle of view takes a while, a user sometimes misses an image sensing opportunity.